Head torch shorts out 18650 cell while not being used!
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- Опубліковано 25 сер 2024
- It turns out my favourite head torch has a bit of a design issue that relies on anodisation and solder resist as insulators. The PCB is literally rammed up hard against the metal.
Initially I thought this was what had shorted out the lithium cell, but after the video I went further and used a microscope to try and work out where the short circuit had occurred.
The culprit is actually most likely the connection point between the two PCBs. There are a few connections and it looks like a solder ball may have been almost but not quite bridging the battery positive and negative connections. It was black and very slightly charred between the two pads. I think the heat may have melted the solder away and destroyed part of the evidence.
I still don't feel comfortable about the close contact between the PCB and -ve case though.
I peeled more from the end of the 18650 cell and it doesn't look like the end pip has been vented through. It looks more like the heat from the burning springs has burned the plastic and caused a bit of corrosion where that happened. I'm cautious about using that cell now as a high temperature incident could potentially have caused the internal separator films to pull back from the edges of the foils they insulate between.
Shame. I really liked that light. And now I'm wary about using its twin. The PCB against the aluminium is too shady. A shim of plastic could have helped greatly.
I think the cases end cap was applied with a press. There was no really obvious glue, so it may have been a friction fit and the copper clip may have been to mate the PCB to the case for the battery negative connection.
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Head "torch" almost turned into an actual flaming torch.
If he was wearing it at the time, it would've been an actual "head torch"!
Yeah you wouldn't want that to happen in a gas filled cave either
Blimey! There are many places you don’t want a lithium cell going thermonuclear. The forehead is definitely one of those places!
Anthony Cooke in your front pocket is much worse. 💥
@@wraithleader2906 crispy balls afterwards
I was thinking the same. I wouldn't want one strapped onto my forehead.
In fact, the only place I would like a lithium cell to go thermonuclear is my enemy's buttcrack.
Just a head warmer in these Winter months.
Reminds me of a watch where the "QC OK" sticker inside was essential insulation of the battery spring. But then there were the IBM har drives where glue from "QC OK" evaporated onto the platters...
Any more info on that IBM HDD Recall because of QC Sticker Glue depositing on platters? Ive heard this quote dozens of times even a decade back when I was still an apprentice but I never could trace it back to some kind of source. Not claiming that it never happened I just want to read more on that topic :)
@@G4m3G3ni3 I don't think you'll find any documentation. Your best bet would be an employee who used to work in their hard drive manufacturing division. But even that would be hear say. Ibm prolly would not release info on this.
My daughter in law is a IBM chemical engineer in Vermont and I think I rember her saying something about that . Think it went way over my head.lol
I'm gonna start research on this, I fancy myself as a historian of odd useless knowledge, and I think this'll be a nice challenge.
The quick escalation in tools used to open this device had me cackling.
Vise of knowledge: 1,000 : Hard to repair devices: 0
It’s unfortunate this thing is so poorly isolated because I am sick of eBay headlamps with there never ending strobe features! Great video 👍
I agree, I love a good head torch but most are so over complicated. I would like a red light and white light on a sliding (but good quality) 2 way switch. The market is swamped with flashy crap.
Steve Marshall yep gearwrench makes one with a 3 position switch on low and high it’s fantastic!!
Why is it that so many 18650 lights have those strobe modes anyway? It seems almost all of them have it! I gave up trying to find a decent flashlight that is just on/off because they're so hard to find. I may try to make my own at one point. An 18650 cell fits perfectly in 3/4" copper pipe, so it's a nice base to get started off of.
@@redsquirrelftw they all use the same logic chip. they have a chip inside to control the current to the led and they have a memory with various modes.
Red Squirrel I agree I bet it’s because those bright power chips that drive the majority of these light have that functionality built in possibly 🤷♂️
I love it how you ramp up the voltage to twice it's normal working voltage, to test where it's shorting out, whilst holding the very thin circuit board between your fingers - with every chance of pressure popping the IC and sizzling your fingertips. A good ounce of bravery that!
I'm really surprised that there was no reverse polarity protection considering how lithium cells can be quite outspoken about being made unhappy.
Don’t use Efest 18650’s they’re notorious for venting.
I own a vape shop & in order for me to get insurance one of the deciding factors was if I carried that company or not. Could’ve been a fine battery, but if the wrap was torn on the positive end.... venting occurs
These are the facts. Search "Battery Mooch" in the vaping forums/reddit for his testing on E-fest batteries and his disgust for this company is pure.
Jeff Carter wow you know it’s bad when the insurance companies step in.
Lying in bed ripping my 220w rda with two of them sat in my unit, very worried now
Don’t trust any battery with fire in the name.
This manufacturing oversight has enraged me. I shall write a very stern letter to eBay and CC all it's customers.
If you manage to non destructively open the other one you could protect the board with plenty of kapton tape which obviously should've been done from the factory
I've been testing whether some strips of plastic can be slid in from the battery access end. Someone else also suggested using a protected 18650 cell.
@@user-gx6jb6wc5g Or you could anodize the interior? jk
@@user-gx6jb6wc5g Could you inject some conformal coating down there?
@@user-gx6jb6wc5g I have had the same problem on the £2.50 "XM-L" (not really) eBay torches. The positive spring is awfy close to the (negative) body contact spring. I 3D printed a nose cover for the cell, that only allows contact to the button in the centre.
There are two items to address: accidentally turning/leaving it on, and accidently inserting the battery, negative first. To protect against backwards insertion, replace the cap spring with one or two cap contacts that are well off center and only able to make contact with the wider, negative battery end. To prevent accidental turning on, remove cap, insert thin plastic disk (cut from some product packaging) covering the negative end of the battery and replace cap.
RIP Big Clive's favorite headtourch
Truly scary... with the incredible popularity of rechargeable devices containing high capacity (high energy) lithium batteries, often with sub-par manufacturing quality control, it is only a matter of time until they become a cause of house fires, even if not in use or being charged. Lithium batteries in the 2020s are going to become the danger 1970s aluminum house wiring became in the 1980s.
It's already a problem and does cause house fires. and is why you can't put them in air plane cargo.
How is it that this comment was made 3 weeks ago when it's timestamped for today, Nov 29?
I was thinking this a few days ago. How much old crap goes up in the loft or stuffed in the cupboard under stairs. Especialy now so much chinese tat uses so many reclaimed or shit to begin with 18650s etc etc.
This is not even a manufacturing problem, it is a design problem. Or actually the willingness to sell faulty goods.
Note that not all cultures have the same approach to safety. Some ride 4 on one motorcycle. Others insure everything twice.
And there's the enthousiast folks: "my drone can't crash, it has low battery detection and autoland" - well Sir, there are many other ways...
@@CassiaConvolution i think patreon supporters get early access to his videos.. theres are a few comments from 3 weeks ago and big clive replied to a comment 3 weeks ago
There was a recall on electrically heated underware that used the very same battery holder. Great balls of fire.
I was really looking forward to seeing what comes after the Dremel tool.
Oh man, so many implements of enlightenment were used here!! How exciting!
Hey clive, the springs are what prevented thermal runaway. because of the heat they compressed/shrank to the point where it couldn't complete the circuit.
I've made some "powerful" flashlights which draw way too much current for the little springs (up to 15A with a single cell is the highest so far) and lets just say i've been there before... we flashlight "enthusiasts" get around that issue by using better quality springs and "bypassing" them with a stranded silicon wire connecting to the end of the spring and to the base so that it remains springy but can handle much more current. (also lowers resistance so that a FET or direct drive flashlight can be a bit brighter)
If you're looking for a new headlight, Skillhunt is a very well liked budget brand around the enthusiasts. the H03 variants are very popular.
On a somewhat related note, it still boggles my mind how the hell those PCB-solderable metal clips that are meant to hold regular batteries are still on sale, legally - those things short out batteries BY DESIGN. In addition to touching the two poles of the battery they also clip onto the cylinder itself - which would be fine except there still are batteries around that have a *lacquered metal* cladding, not a plastic one; and as soon as the super-thin lacquer layer is scratched by insertion on both ends, you have a straight path from one pole through one clip onto the metal cylinder onto the other clip onto the other pole - so you can have a battery start getting warm with nothing but the two clips attached, right in your hand! Which of course actually happened to me with the first battery I tried these accursed things with. Also - the same thing can very much happen with plastic-clad batteries too, it's just somewhat less likely the comparatively thicker plastic cladding will get damaged on both ends. But if it does, same thing...
I bought a couple solar powered motion sensing lights like you took apart a few months ago. Saw one with a popped out side panel LED so took down the unit it to reattach the LED panel. Turns out the 18650 battery shot out an end cap and a spiral of paper/electrodes, physically damaging the housing! Glad it didn't set my shed on fire.
Interesting and alarming at the same time.
7:51 "Oh so it's still working!" Pity you've just done a hatchet job on the case LOL
Likely simple explanation: Raw springs are inherently dangerous around the pos end of an 18650, particularly on a screw cap. There's only around 1-2mm between neg and pos (case and pos cap) at the pos end. It's extremely easy for a spring to displace / unwind and short the cell.
Edit: your hypothesis about board shorting to case is also plausible.
Clive's version is not really a hypotesis, since the burn mark on the PCB is obvious. It shorted out at the front PCB.
@@mrnmrn1 To me, the greater thermal damage was at the spring and pos cap of the battery. If shorted there, the thermal damage on the PCB could maybe be secondary from attempting to charge it (I can't remember for sure if he described a charge attempt before opening it and seeing the damage on the cell).
@@Murph9000 I think the reason for the springs has the most damage is because they're a long string of thin steel alloy wire, so their resistance is much higher than the PCB trace. The postitive end cap of the battery is possibly damaged by a vent event, and possibly the vented fumes were ignited by the red hot spring.
The problem with your theory is that both springs were toasty fried, indicating they had passed considerable current. If it had been a short of the positive terminal then only one spring would have been heated to such an extent.
Lucky that battery has a safety circuit built in or it would have exploded and probably set something on fire. Had a 18650 nearly explode in my hand the other day as i was chucking it out the window after a short circuit occurred and it has began to smoke. You have to be so careful with these batteries. Dont forget the entire outside of the battery is negative and only that small part on the top is positive so its so easy to short them out.
That's the reason why i use a protected 18650 in my Alonefire flashlight. A brand with fire in the name indeed but very good! :) Quality looks really nice and there goes also always a extra plastic protection around the 18650 delivered by the torch. You could also use it with 3x AAA in a converter. But also then is protected 18650 a good extra safety feature
1 it's a lemon (lomon?)
2 the battery label has flames
What did you expect?
Funny that, I live in Lemmon South Dakota, USA. Nice town, named after a cowboy who owned the ranch land where the RR decided to build a train station to put on water and coal.
@@JerryEricsson Cute, did you ever meet Jack?
I only use LEDlenser torches, because I am convinced that these are the only really good torches. As a head torch, I use a MH3, which takes one AA cell, has 2 brightness settings (when you don't change it for a certain time after pushing the button, you don't have to cycle through it to turn it off), and no more bells and whistles. But it has a really great and bright light, which can even be focused by rotating the lens (I don't need that feature, but it's cool to have).
Clive. Sorry for your loss, it's horrible loosing a good friend.
But you had me thinking, of all the torches I've owned that you stuff the batteries in like that one, they all had the battery going in + first.
efest misrepresent their battery specs so that probably doesn't help
Worst Batts on the market
They are the worst, there is a vaping channel which covered this particular brand venting under load.
I wanna see you make a steampunk polished version with copper and soldering now.
The basic geometry really is kinda simple.
I have 3 of the same kind. For the price they are very good. I have used them a lot for over a year now, as i work with stuff during night and there is no electricity around its gets very dark early at this time of the year (northern sweden). So far they have worked perfectly, one battery ain't what it used too and the rubber at the charge port fell off on all of them after a few charges, the ring at the led gets loose sometimes. Besides that it's all good. After seeing this I won't have all three charging beside my bed all the time... Great video.
I recommend fitting them with protected cells. That way the DW01 chip should cut off in the event of an incident.
Thank you Clive. I enjoy a good autopsy, though you do not come to a certain diagnosis but rather the conclusion that the torch is just garbage, with which I agree. This particular torch seems to be a mere prototype that was rushed to market. At this point in time plastic would be the best material for the case, if we exclude environmental concern from the equation. Machined aluminium for a torch is just archaic and more marketing hype or "steampunk" than anything else. I have owned a couple of Maglites. Great art but absolute nonsense.
Negative earth is pretty much the standard for DC systems, since about 1960. The battery compartment cap, if you notice, grounds the battery case to the torch case, so it is a safe bet that the negative end of the battery belongs at the cap. The battery's positive end has a very small dielectric gap to its surrounding case. You are right, if you think that the cap spring shorted the battery's positive pole to the battery's case. They are incompatible. The large negative surface on the other end of the battery could have also shorted to positively charged metal on or around the circuit board.
LEDs are diodes, so correct polarity is required for them to emit light; right? This is not to say that the circuit board could be designed to correct for a reversed battery but that could be suicidal in a single-insulated system, with some of the solder so close to the case.
I have a far superior head torch that is mass produced by a battery manufacturer, Energizer, which was perfect in all but one way, ironically: wasting batteries. Its big momentary button switch would accidentally get squeezed on, in my backpack, briefcase or pocket. So I always carried spare batteries on desert hikes in the mountains, after having repeatedly discovered fully drained batteries. I remedied this design flaw by making a plastic battery isolater out of a bit of stiff plastic product packaging. It is just a strip, 5/16 inch by 1 1/4 inch which I slide between the positive end of the battery and the terminal. It folds 90 degrees to lie flat on the battery, and I snap the case closed, to store. Batteries seem to last forever now.
I had the same problem with a night scope I had. It was a Gen1 thing but still a nice thing to play with at night, a bit grainy and limited vision but you could still make out what things where. It had an infra red LED for 'lighting up' the area in front. I must admit the instructions did say to remove the batteries when not in use, but I obviously forgot about it and it was sat on a shelf for ages until I went to use it again and saw the battery cover was warped and the 2 AA Alkalines were utter destroyed and had ruined the contacts and of course the thing wouldn't work any more. I took it apart and those night things are really weird. It has an anode wire and must work like a TV Tube in reverse, gathering light, amplifying it and focusing it onto a phosphor screen. It's a shame and was an expensive lesson to learn and I don't think I would buy one again. I don't know why the batteries shorted out but they clearly did for some benign reason lol :)
Clive, the little spring on the round circuit board is correctly off center, but the one on the screw-in cap is not.
That one, for obvious reasons, is perfectly centered, so not hitting the center of the battery.
Not an issue on the negative.
But if you inserted the battery with positive toward the cap, screwing it in might have allowed the spring to get through the insulation and short the cell on the + side directly ...
The main source of heat looks to have been there.
Could it be that the torch was almost fine, just the plastic liner and the spring suffered a bit from heating because of puncturing and shorting the cell + insulation with the cap's spring?
I've found that every flashlight, or any other thing requiring batteries... The negative end of the battery always goes toward the spring.
Sadly there are exceptions
But with this torch there is a spring at either end.
and just to fuck with you a large portion of lithium cell flashlights either have 2 springs or a spring on positive and a tab for negative....
Yup. That's why I said, "I've found"... I figured there had to be exceptions. =0)
@@selador11 _The Springs at both ends were probably designed by the Stupes that commented above._
Get a Fenix HL55. I've used mine for several years as a mechanic without battery problems or failures. It doesn't have the IR on/off though. No flashing modes either. Just some brightness levels and it remembers what setting you left it on. Nice flood area effect light, no dark rings in the beam. Also, it takes 18650 batteries.
HL55 me too. I was so happy with it I also bought the recharging version HL60R, but that was a mistake. The extra functions weren't worth the loss of simplicity.
Battery guidelines have always stated that batteries should be removed if not using a device for an extended period. Modern advice for lithium powered devices recommend removal of said batteries where the device will not be in use for 7 days or more.
I'm watching this while on the NYC subway controlling myself from screaming at my phone "tighten the vise of knowledge!"
can a protected cell help here ?
Yes. It would hopefully cut off if the current was high enough. That's a good idea, because I really liked this light.
@@user-gx6jb6wc5g a protected cell saved one of my vintage Lego motors that was stalled
@@user-gx6jb6wc5g videos of bike batteries going off is scariest thing if its inside your home
@@girlsdrinkfeck Lois Rossmann also had a scary video when his bike battery caught fire in traffic.
@@user-gx6jb6wc5g those efest cells are very sketch, lg, Samsung and Sony are what I trust my face and hands to
I think the idea of using a cylindrical O ring sealed sealed aluminium casing for a torch probably began with the American designed Maglight.
Many other companies like FENIX and LED Lenser followed the same format. But used a battery casement and switch module. So they do NOT use the case as part of the circuit. However even with that format; I have had problems with some pretty expensive ones. Yet my cheapest LED torch £5 has been very reliable and that DOES use the metal body as part of the circuit.
Hi Clive,
Here is a thought.. I think like the makers of the head torch expected the reverse polarity protection to just short out the cell with a diode and rely on the PTC in the cell to limit the current... except that since the torch was designed 18650s without any PTCs (or ones that trip at many 10's of amps) are now common, such as your Efest... When the fault happened, the battery spring did got very hot, losing its temper so breaking the circuit like a thermal circuit breaker. This unintended (and fortunate) "feature" of the battery spring may have saved you from the "lithium Battery incident".
Applying a short to a battery pack can cause battery springs to softened the plastic they are mounted on and , break the circuit that way. This is the fun part of product safety testing :-) The LED looks like Cree XM-L.
_Clive they'll short out on their own. I've had a couple of unopened, "Trust-Fire" 18650 2-packs from the cheap Chinese Flashlights, have 1 of them get burnt just sitting in the box._
_I've cut the blue outer covering off some of them only to reveal a black heat shrink covering that says "Panasonic"._
A very serious design flaw in an otherwise nice light. Lithium cells pack a ton of power and you really don't want all that power released as heat on your forehead !
They could've easily solved the issue with some extra insulation above those solder joints.
I love the flash function on headtorches. It anoyes the out off my co workers when I talk to them.
What's the point in annoying someone at work?
Is love a flash function?
Downside is if someone passes with epilepsy it could cause then to have a seizure then fall and death is always a possibility after a fall so you could potentially be prosecuted with manslaughter
@@upsidedown4155 downside up.
If you talk the way you type, I bet that is what is annoying your coworkers.
I kid, I kid It's definitely the strobing...
I guess you could apply some kapton tape to the upper side of the PCB and any other problematic areas which may short and that will "fix" the design problem. It will be effectively insulated and the kapton is thin and sturdy enough to withstand the use and any potential heat.
Suggested design improvements within concept and price limitations:
1. Positive contact is just a bare pad on a PCB, optionally pretinned.
2. Non-ground tracks are run mostly on the inside, using the PCB itself as isolation.
3. Pushbutton is replaced by a touch contact on the outside of the bottom PCB.
4. Inside surface of PCB covered by strip of electrical tape.
5. No waving detector.
Clive you are an electrician.. you like the light and how it functions.. insulation and modification is the answer :)
I have another. It will be modified.
If you want something to go BANG!!! you could do what I accidentally did 25+ years ago in High School Electronics class...
We had to build an Electronics Kit (I choose a huge digital clock) and accidentally wired the Step Down Transformer in backwards...
It was supposed to take the 120V mains and drop it to 5V...instead, it took 120V and stepped it UP to 2,880V...1st time I plugged it in there was a BIG BANG and a simultaneous thud above us...
The transformer got literally blown off the board and embedded in the drop-ceiling tile above me...Scared the hell out of myself and the Teacher...
Surprisingly, after replacing the transformer (and making DAMN sure it was wired in properly), everything worked...still have it in fact, but I need to replace the LED's of the display board...too bad. the think was so bright I didn't need a Night Light... :D
You should insert the battery with the negative end touching the spring. The spring will force its way in between the positive contact point and the negative rim if you insert the battery the wrong way.
I use a headlamp with three lamps where you can adjust each one individually (only vertically). Really nice thing from Aliexpress for like 15€.
Adjusting each lamp individually is really nice, because you usually not turn your head most of the time but just your eyes. So for example I put the smaller lights downwards more, so I get light there. Can highly recommend such a headlamp.
One would think that anyone who's seen a careless vaper with his trousers on fire, would think twice about strapping an 18650 to his forehead.
Another interesting video as always Clive :)
Clive the cell has vented as it has probably overheated they have an internal pressure relief in the cap. Don't touch the electrolyte!!! It is likely flourinated and will burn you and stain you black. Always wear nitrile gloves when handling questionable Li-pos. Get a viton burns kit as this can neutralise such a burn. Lucky it didn't go up in flames, the newer higher power density ones are not so forgiving.
efest cells. dont buy anything other than sony, lg, pannasonic, samsung.
Imren 40a batteries last even longer than samsungs 30Q :D
And buy from a reliable seller - there are lots of crappy Chinese counterfeits on Amazon and eBay dressed up in "Panasonic" wrappers. Too-good-to-be-true prices are exactly that.
@Против Глобал Turnigy is a trustworthy brand.
Hi Clive, I share your passion for finding a pearl in chinese pile of turd, but for such an often needed tool that I put on my forehead in an inch of my eyes I prefer the cheapest PETZL. This model use to be called TIKKA but quick googling showed there is a new generation of the model and there is now an even cheaper model called TIKKINA. It's plastic, it's not particularly bright, it's relativelly expensive, but it's lightweight and the thing that goes south first after intensive use is the very soft and nice to touch elastic band, however it does not degrade ugly, but just stretches and becomes partially loose which is easily compensated. Not a comercial, I'm sure there are many other reliable brands.
My first LED head torch was a Tikka. The build quality was appalling. The switch was a plastic pin that pushed a battery contact against a resistor lead. It was probably their first LED unit. I think they've improved since then.
@@user-gx6jb6wc5g Well, mine example has metal tactile dome pushed by a rubbery button moulded together with the hard transparent plastic of the body. It doesn't matter anymore, - the current revision looks rather different from mine. I've just opened it for the first time just to check against your description :)
The spring usually contacts the ground or negative.
I'm fairly sure Clive is aware of that, but in this case there are springs on both ends. Probably so you can use it with plain cells (that don't have a "nipple" on positive).
In this case the inside spring was positive, which is really unexpected
I'd say the inside being positive was the most likely option (because the negative is more likely to be connected to the case, and it's easier to connect the lid to the case than it is to route it to the positive connection _without_ touching the case), but they should still have labelled it.
be glad it didn't short out and catch fire when it was on your head also the spring acted like a fuse on the negative terminal it should of had a different insulator and batteries don't like short circuits
Also note: Lithium cells can randomly short out internally. This can be encouraged with over charging, over discharging or being dropped. That is why every one of the 8,000 or so 18650 cells in a Tesla Model S battery pack is fused. If one cell should go screwy the energy of the 90 or so paralleled cells wont dump into it.
Are you talking about a thermal runaway scenario
@@yfs9035: Not necessarily. That is the extreme situation. This cell heated up enough to cause an electrolyte spill which appears to have stopped the full meltdown and catch fire bit. Batteries are chemical devices that just happen to produce electricity. And are never off.
@@randycarter2001 Oh. Thanks for the wisdom
The housing will be positive when you put the battery in backwards. It looks like the sleeve around the battery was damaged, this exposes the "unsleeved" metal of the battery that is negative. You will get a short circuit if that unprotected metal part of the battery comes into to contact with the positive housing of the lamp, when you put the battery in backwards.
I've got a headlamp which takes a single AA that comes on in a low power state when the battery gets low, slowly flattening the battery even more.
Sounds like it was made by a battery manufacturer.
Those purple E-fest batteries are kind of notorious in the vaping community for not meeting published specs and being unsafe. Also with 100% mechanical vaping devices, springs are always on the cell's negative.
11:42 Oh! That's a bit disappointing that's not supposed to happen, it's supposed to go bang! I hope that you kept your receipt? Ha ha
You are lucky the battery's thermal fuse worked as it was supposed to when the battery was shorted out and stopped it from turning into a fireball. At least, that appears to be what happened, judging by the state of the positive terminal.
-Matt
I'd highly recommend the Nitecore NU25 as a replacement. It's lite, multi-functional, USB rechargeable and very bright.
I was looking at headlamps for a gift and came across one on amazon that had 2x 18650 cells in a plastic pack on the back of your head with the light up front. One of the comments was that it was had a hard wired parallel connection with no reverse polarity protection so if you put one cell in backwards it would be in full short with the other one. Nice. If a UK manufacture wants to make a product they have to meet all kinds of stringent safety regulations but chinese stuff on Amazon is made to whatever standard the chinese manufacturer decides which usually means nothing with the fake CE logo slapped on it.
I recently bought one on eBay, it's fantastic. I don't replace the 2 batteries, because they're in parallel and if I accidentally put batteries with voltages that don't match it could go bad.
But I don't think you can put one backwards, specifically in mine, the metal tabs are concealed behind plastic fairly well.
I charge it with a TP405...somethingmicro USB module.
In my 63 year of battery powered experience, its always the spring at the negative end of the battery.
It has springs on both sides.
May be your first battery was a protected 18650 - > short circuit protection kicked in
Dremel, spanner, blowtorch, genteel deconstruction, or what?
Clive another fantastic,, informative and entertaining production. Thanks for sharing
I have an early gen led lamp (Tesco... Who branded tech! :) that seems to have been the source of my tears of x10 lighting gremlins.read sinetgi g about filtering online but never did anything about it. Also a 13a through adaptor with 2xusb sockets. Never worked. Just send me a sign, it would be a pleasure.
Cheers from the fatherland (unwanted relation that is the disfunction uk
Gary from England
Solder joints on the board could be making contact with the metal body, same as with some of those cheap pen light things B&Q sell
The springs make excellent heaters in case of a fault. The scaring has nearly disappeared now. End caps and their springs are - only.🤕
In my experience, negative usually goes on the spring
*Hey Clive, could you try to open the other one in a way it's not destroyed, so we can learn how to open ours?*
I have one like those, different model, when I realized the battery cap just touches the battery negative and then the case itself and that's all it needed to transfer the power, it gave me the chills. Also tried, unsuccessfully to open mine, and maybe try to insulate whatever was in risk of touching the housing. Your video just confirmed my suspicion, that channeling the negative of the battery through the case is a bad idea. Maybe we could make ours safer, if we could open it?
Hey Clive, does that head lamp have any protection circuitry built in? Because it would appear when you pulled the wrapper off, the cell did not. If the cell was discharged under 3 volts a few times, that may have caused the electrolyte to crystallize and create a short inside the cell itself. Not saying that is what happened, but it is a possibly.
I wondered if it was only me! I have lots of chinese pixie cages that don't make it at all clear which is the takeaway and which is the shitter.
I got a mini belt sander that's just a motor a switch and a speed control. I spent the first week making things thicker and not thinner. It came un-connected - you just had to connect a couple of spade connectors. The motor and switch had red and black dots carefully applied to each terminal. Unfortunately all the wiring was red, and it seems switching live is for wimps.
My battery dremdrill is excelent for £9.99 - but no-one said that the spring was +, its quite exciting the first time the chuck unscrews itself and a cutting disk flies over your shoulder doing 15000rpm.
Even with duracell's best this was only ever a mild irritation - but now we are in the century of the thermonuclear Lilon incendiary it's a bit more of an issue.
Do you think that c clip was locking the cap on? If so maybe it could be removed without damage and properly insulated and reassembled. Looks like a very nice light if not for the lack of insulation.
Weak link in the design.
And I have the same one. So, is changing the battery causing the wear on the anodized layer? I'm trying to think of a reason to keep using mine, but if I do I'll definitely charge it in my explosion resistant cookie tin. I actually charge everything in those now.
One of the best ideas I've learned from Big Clive.
"...no flashing mode..." Well. Why would you even keep it around? (sarc)
Bane of my life, oh, thats a nice torch, ahh ffs, another one with a fucking strobe. And ambulances, why are they soooo fucking loud! They need a soft start on the siren, they almost give ME a heart attack.
Ambulances are that loud on purpose to tell you to get out of the way *NOW!!* Someone could be seriously injured and every second matters.
Perhaps you could get the other one apart and keep the end cap intact, then put kapton tape over the circuit board and re-assemble? Seems a good torch apart from that one flaw.
I had one of these head torches. It delveloped a fault where the light was flickering so i took it apart to try to fix it. The end cap is just a press fit on the main body and requres a good hit on alternate sides to get it off. The brass coloured ring should be soldered to thd round ciruit board and I beleive is intened to create a contact between the main alumium body and the cirtcit board to complete the negative supply to the board. In the end I couldnt get it to stop flickering and it eventually it failed altogether. Also, it was not at all water resitant, the usb port and holes for the IR transmitter and receiver being the areas that will easliy let water in. I have replaced my old head torch with a different model that again uses an 18650 battery, incorporates usb charging but does not have the IR facility. The USB port on the new one is located under the end cap that partially unscrews to reveal the port and has o rings to provide some water resitance. It is more compact and weighs less than the old head torch, has 5 brighness levels and cost the same. Easily found on ebay from a number of different sellers.
Believe Olight also makes a headlamp that has simple features and I believe it has a red night vision mode but it’s very pricey over $100 but olight is the Cadillac of the Flashlight world so I don’t think they have any torches that are below 50 bucks.
It still works.
Cover the board in silicone and slap a protected lithium cell in it .
You'll be fine.
Design-wise, a soft springy +ive terminal is also a very bad idea. If the pointy end of the spring works it way under the wrap or the insulator ring to the -ive case only a fraction of a millimeter away, an instant short circuit is the result. Most batteries do not have the insulator ring glued in as that one appears to have - most are just a plastic ring held in place by the wrap.
Remember this applies to DC power, Commonly if there is a spring that is connected to the metal body its the negative,
Clive will know this but just putting it out there as reckon its simply a oversight as he is extremely knowledgeable with electronics and i will never say a bad word about him,
I dont know a quarter of what he knows and unless the day comes that i know more i will always have faith in these videos
Also imagine if it popped like those vaps with dodgy batteries, almost guaranteed blindness as your eyes would be mutilated by the debris and chemical fire
There was a spring contact at both ends of the battery.
DO NOT use a battery showing that damage.. or any indication of having over heated.. I build power packs with 18650's and if you have one that overheated, it most likely does not have a protection circuit and if it gets that hot, it has shorted internally. Throw it away even if it wants to hold a charge.
I'm glad you made the knife safer by going VVVVVVVVV, it makes all the difference
I feel like mag lights do this too! They get warm and also they don’t last very long. And don’t even get me started on the crappy keychain ones! They last a month or two at best with limited use.
I could not see any discolouration at the point where you suspected it to have contacted the casing, shouldn't there be some? Could it have been the solder blobs in the intersection of the boards contacting the end cap, the spring clip or some other part in there?
Looks like it had an internal spring clip that retains it. I've used similar clips in my designs when they're not meant to come back apart. Makes assembly convenient, but its pretty much trash if you f up. Also the spring clip itself may also have been the alignment mechanism if the groove in each section doesn't go all the way around.
I am no expert but ... looks like you need a new head torch there. Just a heads up 🤣
I purposely reversed mine once because the led was remaining on very low and was once told reversing would " straighten" out the problem. Immediate overheating. I was able to shake out the batteries before ruining it, however the springs had both become "un springy". I stretched them a bit put the batteries in right and it worked fine, albeit with led still low when off. Pretty sure it would have gotten vey nasty if left in, however batteries didn't get hot, just the springs.
Sounds more like a ghost led and circuit, they just never fully turn off from manufacturing flaws
@@benson4u215 yes, since it worked fine for about a year, something had to have gone bad. I'd been removing the batteries to prevent draining them. Sadly/fortunately I've misplaced headlamp and ordered a new one that hopefully will not have the same issue. The main reason I posted was I was surprised at how quickly the reversed lion batteries heated up turning the negative springs red hot in seconds. I'd done the same by mistake with AA alkalines with no heating issues at all, just put them the right way around and everything worked fine.
Same thing with those XHP clones on eBay. Nothing to tell you which way the cell goes in. Luckily for me, only the USB charging circuit was destroyed.
I know from experience with cheap powerbanks, those spring terminals really don't like much current. I've had a few glow and one melt.
A "lithium incident" is the kind of term I'd expect Tesla or Boeing corporate to use with reference to Dreamliners and Tesla cars wholly or partially combusting.
Well efest Batts have been known to be trash and dangerous cause they're not rated properly
Hey Clive. Which bench power supply are you using? I’m looking to get one.
Olight H2R best one I've used yet.
I agree the H2R nova is brilliant
Fenix HL60R (I have a special Finland only model)... H2R seems great exept the output drops from turbo to too low
Weird 'cos the Chinese are famous for their quality and safety....
The cheaply made internals could pull more amps out of that quality cell then the tail spring could handle, then the front spring had the same issue.
Solder a piece of solder wick from the tip of the springs to the base of each, then you can suck the juice out of the cell faster without worry.
Since you have already ordered a new one...check it out...they may have addressed this issue in a newer unit.
Well that is a bummer. Clive do you recall the head torch that has the removable USB lamp with the two 18650 cells? I want to taaaaahank uoi for showing that one. It has become my best friend when working on cars when a large mains powered lamp is more of a pain to deal with.
Its when they start sticking these in toys is when things really go wrong. Although one exploding within millimetres of your face as an adult is also terrible.
Well done, Mr. Holmes "Clive"